"Half of the French want it."
Translation:La metà dei francesi lo vuole.
In English, "group" is a collective noun and can be either singular or plural, as MikeLyons85 points out. Half a group shares this usage, but usually "half" of a group is plural (unless it is a "group" of only two or is referred to as an entity). The use of a singular verb is a logical fallacy, and therefore ungramatical. But in Italian "la metà" is always a singular entity, not a "count" word. English has a similar usage in mathematics: we say "half of four IS two," just Italian says "La metà di quatro È due." Italian always uses "metà" in this way. The word has a plural form ("le metà), which can be used in phrases like "Le due metà della mele sono uguale" (The two halves of the apple are alike), but each half is singular, just as "La metà dei francesi" is singular.
It may help to remember that "metà" also has the sense of "midpoint/half-way-point/middle" which is unequivocally singular in both Italian and English.
As it seems rather complicated I refer to this excellent post: https://blogs.transparent.com/italian/meta%E2%80%99-or-mezza/
For folks that are confused with meta vs. mezzo I fond this. http://blogs.transparent.com/italian/meta%E2%80%99-or-mezza/
I believe you have identified the crux of the matter nicely. The Italian "la metà di" is best thought of as "the one half of" something. So it is singular, even if what it subdivides is plural.
The one half of an apple, would be a singular apple half (equal slice). The one half of a million people would be a singular group of 500,000 people.
I don't know if there's actually a pronoun, but we use this sort of phrase in English often in the singular.
Ex: Half the crowd IS in the stadium and the other half IS waiting to get in.
In British English, collective nouns can be either singular or plural, depending on context. "The government has decided" means that there is one view that has been agreed, and that has been announced. "The team were so disorganised" means that the individuals were all over the place and not pulling together. Here "La metà" clearly refers to millions of individuals, so the verb is correctly plural in English.
Is the plural of people (or french people) automatically masculine or can this sentence also be written as "La metà delle francese lo vuole"